1. Field of the Invention
The present invention relates to a cap removal apparatus and a cap removal method for vacuum blood collection tubes, configured to automatically remove caps from vacuum blood collection tubes that contain collected blood.
2. Description of the Related Art
A test tube that contains blood has its opening closed by a cap, such as a rubber cap. In a blood aliquoting/dispensing apparatus, for example, a large number of test tubes are supported one after another by test tube holders or the like and conveyed by a conveyor belt. When the test tube reaches a cap removal position in the course of conveyance, the conveyance of the test tube is temporarily stopped, and the cap on the test tube is automatically removed by a test tube cap removal apparatus. The uncapped test tube is conveyed to an aliquoting/dispensing position by the conveyor belt again, whereupon the blood in the test tube is aliquoted and dispensed by the aliquoting/dispensing apparatus.
In a test tube cap removal apparatus described in Jpn. Pat. Appln. KOKAI Publication No. 2005-271991, for example, a cap on a test tube held by a test tube clamping mechanism is chucked by a chuck mechanism. Thereafter, the chuck mechanism is raised by a lift mechanism so that the cap is removed from the test tube.
In the case of a vacuum blood collection tube formed of a decompressed test tube that contains blood, the atmospheric pressure outside the collection tube that is kept under vacuum inside rushes into the tube the moment the cap is removed. Accordingly, the surface level of the blood in the collection tube is depressed by the atmospheric pressure, so that the blood splashes out of the collection tube and adheres to peripheral devices or adjoining collection tubes, thereby causing contamination.
The present invention has been made in consideration of these circumstances, and its object is to provide a cap removal apparatus and a cap removal method for vacuum blood collection tubes, capable of easily preventing blood from splashing out of the collection tubes when the collection tubes are uncapped, thereby solving the problem of contamination.